The invention discloses a plate butt connection device and method. The device is characterized by comprising a base, a supporting column I and a supporting column II. The supporting column I (2) and the supporting column II (3) are fixedly installed on the base (1). A clamping sample hole I (4) is formed in the supporting column I (2). A clamping sample hole II (5) is formed in the supporting column II (3). A cylinder (7) is fixed to the tail of the clamping sample hole II (5). A lead screw (8) is driven by a motor (9) to rotate so as to move in the cylinder (7). A heating groove (6) wraps the butt connection position of a workpiece I (13) and a workpiece II (14) in a bearing mode and carries out heating. Both the heating groove (6) and the motor (9) are controlled by a controller (10). According to butt connection, the mode that connection areas of plates are plasticized through large-power friction is not needed, the connection areas of the plates are made approximate to the melting point in a heating way to be plasticized, then, connection is achieved under external extrusion force in a slow extrusion process, and a connector is good in performance.